Near the time of an election, a cable news service performs an opinion poll of 1,000 probable voters. It shows that the Republican contender has an advantage of 52% to 48%.
a. Develop a 95% confidence interval for the proportion favoring the Republican candidate.
b. Estimate the probability that the Democratic candidate is actually leading.
c. Repeat the above analysis based on a sample of 3,000 probable voters.
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